矿山地表塌陷坑废气治理与环境监测

Treatments and environmental monitoring of waste gas from collapse crater of ground surface

针对广西大厂铜坑矿细脉带火区地表塌陷坑废气排放带来的大气污染及对当地自然生态环境的破坏问题,采用地表硐室爆破抛掷覆盖塌陷坑与地表废气碱吸收方法进行综合治理。通过实施11次地表硐室爆破工程,覆盖总岩土方量为31.85×10~4m^3,同时采用喷浆胶结进一步密实措施形成细脉带事故隐患区的大面积覆盖,有效窒息火区的燃烧。不具备爆破覆盖的塌陷坑则采用氢氧化钙湿式洗涤法进行治理。通过对井口喷洒雾状石灰水,使其与冒出地面的SO_2发生吸收和氧化反应,再渗入塌陷坑内吸收废气,抑制矿石的燃烧。

Due to the problem of air pollution and environmental disturbance brought by waste gas escaped from the collapsed crater of ground surface, it is necessary to develop a comprehensive treatment strategy for Tongkeng mine of Dachang, Guangxi. Based on the analysis of waste gas characteristics, methods of chamber blasting to cover collapsed crater and waste gas absorption by using alkaline were selected as treatment approaches. Through ll times application of chamber blasting engineering with covering earthwork up to 31.85 x 104 m3, large hazardous area was covered by adopting the compact measures of gunite cementation, which have asphyxiated the fire area efficiently. If the crater exists without presence of hillbody nearby, the wet treatment of Ca （OH）2 washing method should be utilized. The fundamental principle is spraying the mist limewater through well-head to make it absorbs and reacts with SO2 emitting from the ground via oxidation. Limewater diffuses into collapsed crater to absorb waste gas and achieves the treatment goal of inhibiting the burning of ore. The article mainly introduces the alkaline absorption process of ore pass 6 and air shaft 2. After the treatment, the large area collapsed crater is covered and SO2 is removed effectively. For a long period of environmental monitoring, it shows that concentration of emitted SO2 was controlled below 5.71 mg/m^3, which has reached the national discharge standard.